The statements in this section merely provide background information related to the present invention and may not constitute prior art.
Dimming for light emitting elements is desired in most application circumstances. Currently, pulse-width modulation (PWM) dimming is commonly used for light emitting element dimming. Generally, a PWM dimming signal having a frequency and a duty cycle is applied to control a driving circuit of the light emitting elements to illuminate/extinguish the light emitting elements periodically, so that the illumination of the light emitting elements could be adjusted to a desired level by varying the frequency and/or the duty cycle of the PWM dimming signal.
A need therefore exists for a dimming circuit that could be conveniently configured by the users to obtain desired dimming signals for controlling the light emitting elements at a desired illumination level. To this end, one embodiment of the present invention provide a dimming circuit that is configurable to operate in different dimming modes so that the users could obtain desired dimming signals by providing a few external devices, such as resistors and/or capacitors, to the dimming circuit.